290 BOTANY.. is supposed to be the Poa Andina of NuttaU, is exceedingly variable and puzzling. It embraces several varieties, two of which are represented in this coUection, viz: Var. spicata.—Radical leaves rigid, involute, scabrous, pungently pointed, 3 to 9' long; panicle narrow and spike-like; branches sessile or nearly so.—Colorado, 1873 (1135, 1136, 1137). Var. majoe.— Panicle oblong; branches short; flowers larger and paler.—Arizona, 1872 ; Colorado, 1873 (1133, 1134). Poa tenuifolia, Nutt. (Watson's Botany 40th ParaUel, Synopsis Flora of Colorado).—This species presents a great variety of forms, some of which may yet require to be made distinct species. The general characters may be stated as foUows: culms tufted, 1-2J° high, stout or slender, glabrous or with the leaves and sheaths more or less scabrous; leaves narrowly linear, 1-10' long, ligule short or elongated; panicle erect or slightly bending, narrow or somewhat open and spreading, 2-6' long; branches 2-5 together, scabrous, of unequal length; spikelets 2-5-flow¬ ered, glumes keeled, lanceolate or ovate-lanceolate, acute, scarious-mar¬ gined, upper one 3-nerved, lower 1-nerved; flowers very narrow, linear or linear-lanceolate, scarcely keeled, convex on the back, obtuse or acutish, scarious, and bronze-tinged at the apex, puberulent or finely pubescent, obscurely nerved, not webbed; flowers readily separating at the joints. The grain is extensively gathered by the Indians for food. The following forms or varieties occur in the collection: Var. eigida, Nevada, 1872, Colorado, 1873 (1138 and 1140) ; var. elongata, panicle linear, 5-6 inches long; Nevada, 1872; Colorado, 1873 (1141). Poa peatensis, L.—Colorado, 1873 (1125) ; Santa Fi, N. Mex., 1874 (19); and, what seems to be a slender form, in bogs, Twin Lakes, Colo¬ rado, 1873 (1131). Poa seeotina, Ehi-h.—Twin Lakes, Colorado, 1873 (1130) ; also var. laxicaule. Twin Lakes, Colorado, 1873. Poa c^sia, Sm.?, var. eigida.—Mosquito, Colorado, 1873 (1142); South Park, Colorado, 1873 (1143). Poa LAXA, Hsenke ?—Colorado, 1873 (1128). Var. minoe. Hall's post-office, Colorado, 1873 (500, J. Wolf). Poa flexuosa, var. occidentalis.—Twin Lakes, Colorado, 1873